Components-dependent optical nonlinearity in a series of CdSexS1−x and CdSexS1−x/ZnS QDs

•The nonlinear optical properties of these QDs were investigated using Z-scan technique.•The nonlinear refractive indices can be tuned by the ratio of Se and S components.•Nonlinear optical (NLO) properties have been enhanced in CSQDs.•The components-tuned nonlinear refraction indices may lead to a wide application.

The different compositions of the ternary alloyed CdSexS1−x and CdSexS1−x/ZnS core/shell quantum dots(CSQDs) have been synthesized by the chemical routes. The nonlinear optical properties of these QDs were investigated using Z-scan technique under the excitation of the 1064 nm picosecond laser pulse. The Z-scan results reveal that the nonlinear refractive indices of these QDs can be tuned by changing the ratio of Se and S components. Nonlinear optical (NLO) properties have been shown to be enhanced in CSQDs as compared to their core semiconductor counterparts. These QDs exhibit the components-tuned nonlinear refraction indices, which lead to a wide application in the photonic field.